Abstract:

An automatic document feeder includes a main body defining a passage for
transporting a document. A feeding roller unit includes a feeding driving
roller and a feeding idle roller coupling with the feeding driving
roller. The feeding driving roller and the feeding idle roller are
disposed at opposite sides of the passage. A drawing-out roller unit
includes a drawing-out driving roller and a drawing-out idle roller
coupling with the drawing-out driving roller. The drawing-out driving
roller and the drawing-out idle roller are disposed at opposite sides of
the passage. The drawing-out driving roller and the feeding driving
roller are at the same side of the passage. And a belt is put around the
feeding driving roller and the drawing-out driving roller to mate with
the feeding idle roller and the drawing-out idle roller respectively for
flatting and conveying the document into and out of the automatic
document feeder.

Claims:

1. An automatic document feeder, comprising:a main body, having a pedestal
and a cover coupling with the pedestal, a document-guiding element
mounted between the pedestal and the cover, a passage formed between the
document-guiding element and the pedestal and cover, which includes an
entering passage, an operating passage and an exiting passage;a feeding
roller unit, including a feeding driving roller disposed at the
document-guiding element and near to the entering passage, and a feeding
idle roller coupling with the feeding driving roller disposed at a side
of the entering passage opposite to the feeding driving roller;a
drawing-out roller unit, including a drawing-out driving roller disposed
at the document-guiding element and near to the exiting passage, and a
drawing-out idle roller coupling with the drawing-out driving roller
disposed at a side of the exiting passage opposite to the drawing-out
driving roller, the drawing-out driving roller and the feeding driving
roller being at the same side of the passage; anda belt around the
feeding driving roller and the drawing-out driving roller to mate with
the feeding idle roller and the drawing-out idle roller respectively for
flatting and conveying a document into and out of the automatic document
feeder wherein the belt is set only to surround the feeding roller unit
and the drawing-out roller unit.

2. The automatic document feeder as claimed in claim 1, further comprising
an image-handling unit disposed between the feeding roller unit and the
drawing-out roller unit.

3. The automatic document feeder as claimed in claim 2, wherein the
pedestal defines a concave supporting-surface extending from a front end
to a substantial rear end thereof, the supporting-surface opens a hollow
recess at substantially the center thereof for receiving the
image-handling unit.

4. The automatic document feeder as claimed in claim 1, wherein the
document-guiding element has a loading portion and a transporting
portion, the junction of the loading portion and the transporting portion
extends outward to form a leading portion, the entering passage is formed
between the loading portion and the cover, the operating passage is
formed between the rear of the transporting portion and the rear of the
pedestal, the exiting passage is formed between the front of the
transporting portion, the leading portion and the front of the pedestal.

5. An automatic document feeder, comprising:a main body, defining a
passage for transporting a document;a feeding roller unit, including a
feeding driving roller and a feeding idle roller coupling with the
feeding driving roller, the feeding driving roller and the feeding idle
roller disposed at opposite sides of the passage;a drawing-out roller
unit, including a drawing-out driving roller and a drawing-out idle
roller coupling with the drawing-out driving roller, the drawing-out
driving roller and the drawing-out idle roller disposed at opposite sides
of the passage, the drawing-out driving roller and the feeding driving
roller being at the same side of the passage; anda belt around the
feeding driving roller and the drawing-out driving roller to mate with
the feeding idle roller and the drawing-out idle roller respectively for
flatting and conveying the document into and out of the automatic
document feeder wherein the belt is set only to surround the feeding
roller unit and the drawing-out roller unit.

Description:

BACKGROUND OF THE INVENTION

[0001]1. Field of the Invention

[0002]The present invention relates to an automatic document feeder
mounted in an office machine, such as a fax machine, a scanner, a
printer, a copy machine, or a multi-function peripheral (MFP), etc. to
convey a document into or out of the office machine.

[0003]2. The Related Art

[0004]An automatic document feeder is widely used in an office machine,
such as a fax machine, a scanner, a printer, a copy machine, or a
multi-function peripheral (MFP), etc. The automatic document feeder
conveys a document into the office machine to have an image handled, and
then, the automatic document feeder transports the handled document to
the outside of the office machine.

[0005]Referring to FIG. 1 providing a conventional automatic document
feeder 200, the automatic document feeder 200 includes a feeding roller
unit 70, a drawing-out roller unit 80 and a document-feeding passage 90.
After the document enters the document-feeding passage 90, the feeding
roller unit 70 including a feeding driving roller 71 and a feeding idle
roller 72 gearing the feeding driving roller 71 feeds the document to an
image-handling unit to have an image handled. Then, the drawing-out
roller unit 80 involving a drawing-out driving roller 81 and a
drawing-out idle roller 82 gearing the drawing-out driving roller 81
delivers the handled document to the outside of the document-feeding
passage 90. Because the automatic document feeder 200 has the feeding
roller unit 70 and the drawing-out roller unit 80, two pairs of gear
wheels which are driven by a power machine such as a motor (not shown)
are needed to mate with the feeding roller unit 70 and the drawing-out
roller unit 80 respectively for carrying the document forward. Therefore,
the structure of the automatic document feeder 200 is rather complex, and
what is more, the manufacture cost and the difficulty of fabricating the
automatic document feeder 200 are increased.

[0006]Referring to FIG. 2 representing an improved automatic document
feeder 300, the automatic document feeder 300 has a document-transporting
roller 100 instead of the feeding driving roller 71 and the drawing-out
driving roller 81 (shown in FIG. 1). The document-transporting roller 100
gears a feeding idle roller 73 to feed the document to an image-handling
unit to have an image handled. And at the same time the
document-transporting roller 100 gears a drawing-out idle roller 83 to
deliver the handled document to the outside of a document-feeding passage
91. Although the automatic document feeder 300 needs a pair of gear
wheels driven by a power machine such as a motor (not shown) to mating
with the document-transporting roller 100, simplifying the structure of
the automatic document feeder 300 and reducing the manufacture cost
thereof, however, the automatic document feeder 300 has only one
document-transporting roller 100 to gear the feeding idle roller 73 and
the drawing-out idle roller 83 simultaneously, increasing a drawing-out
angle of the document, and then, the document is drawn out of the
document-feeding passage 91 not smoothly.

SUMMARY OF THE INVENTION

[0007]Accordingly, an object of the present invention is to provide an
automatic document feeder mounted in an office machine for conveying a
document into or out of the office machine. The automatic document feeder
includes a main body defining a passage for transporting the document. A
feeding roller unit includes a feeding driving roller and a feeding idle
roller coupling with the feeding driving roller. The feeding driving
roller and the feeding idle roller are disposed at opposite sides of the
passage. A drawing-out roller unit includes a drawing-out driving roller
and a drawing-out idle roller coupling with the drawing-out driving
roller. The drawing-out driving roller and the drawing-out idle roller
are disposed at opposite sides of the passage. The drawing-out driving
roller and the feeding driving roller are at the same side of the
passage. And a belt is put around the feeding driving roller and the
drawing-out driving roller to mate with the feeding idle roller and the
drawing-out idle roller respectively for flatting and conveying the
document into and out of the automatic document feeder. Wherein the belt
is set only to surround the feeding roller unit and the drawing-out
roller unit.

[0008]As described above, because the belt is put around the feeding
driving roller and the drawing-out driving roller, the automatic document
feeder utilizes one pair of gear wheels to drive the feeding roller unit
and the drawing-out roller unit rotating simultaneously, and at the same
time, the belt flats the document, which ensures that the document is fed
and transported out of the automatic document feeder smoothly. It is
obvious that the automatic document feeder has a simply structure and it
is easy to fabricate the automatic document feeder. Therefore, the
manufacture cost of the automatic document feeder is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]The present invention will be apparent to those skilled in the art
by reading the following description of preferred embodiments thereof,
with reference to the attached drawings, in which:

[0010]FIG. 1 is a side view of a prior automatic document feeder;

[0011]FIG. 2 is a side view of another prior automatic document feeder;

[0012]FIG. 3 is a side view of an automatic document feeder in accordance
with a first embodiment of the present invention;

[0013]FIGS. 4-7 are side views showing processes of the automatic document
feeder feeding and drawing out a document; and

[0014]FIG. 8 is a side view of an automatic document feeder in accordance
with a second embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015]Referring to FIG. 3, an automatic document feeder 1 in accordance
with a first embodiment of the present invention includes a pedestal 10,
a document-guiding element 20, a feeding roller unit 30, a drawing-out
roller unit 40 and a cover 50. The cover 50 couples with the pedestal 10,
and thereby, an accommodating chamber is formed between the cover 50 and
the pedestal 10. The document-guiding element 20, the feeding roller unit
30 and the drawing-out roller unit 40 are received in the accommodating
chamber. The pedestal 10 defines a concave supporting-surface 11
extending from a front end to a substantial rear end thereof. The
supporting-surface 11 opens a hollow recess 12 at substantially the
center thereof. An image-handling unit (not shown) is seated in the
recess 12.

[0016]The document-guiding element 20 in a horizontally lied sealed
Y-shape has a loading portion 21 and a transporting portion 22. The
junction of the loading portion 21 and the transporting portion 22
extends outward to form a leading portion 23. A passage that a document
passes through is formed between the document-guiding element 20, the
pedestal 10 and the cover 50, which includes an entering passage 101
formed between the loading portion 21 and the cover 50. An operating
passage 102 is formed between the rear of the transporting portion 22 and
the rear of the supporting-surface 11 of the pedestal 10. An exiting
passage 103 is formed between the front of the transporting portion 22,
the leading portion 23 and the front of the supporting-surface 11 of the
pedestal 10.

[0017]The feeding roller unit 30 has a feeding driving roller 31 and a
feeding idle roller 32. The feeding driving roller 31 is disposed at the
document-guiding element 20 and near to the entering passage 101. The
feeding idle roller 32 coupling with the feeding driving roller 31 is
disposed at a side of the entering passage 101 opposite to the feeding
driving roller 31. The drawing-out roller unit 40 has a drawing-out
driving roller 41 and a drawing-out idle roller 42. The drawing-out
driving roller 41 is disposed at the document-guiding element 20 and near
to the exiting passage 103. The drawing-out idle roller 42 coupling with
the drawing-out driving roller 41 is disposed at a side of the exiting
passage 103 opposite to drawing-out driving roller 41. The drawing-out
driving roller 41 and the feeding driving roller 31 are at the same side
of the passage. A belt 60 is put around the feeding driving roller 31 and
the drawing-out driving roller 41 and then mates with the feeding idle
roller 32 and the drawing-out idle roller 42 respectively to bring the
feeding roller unit 30 and the drawing-out roller unit 40 to rotate at
the same time.

[0018]Please refer to FIGS. 4-7 showing processes of the automatic
document feeder 1 feeding and drawing out the document. The processes are
described as follows:

[0019]With reference to FIG. 4, a picking-up device (not shown) is
provided to pick up the document stacked in a document-supplying tray
(not shown) and then the document enters the entering passage 101 and is
placed between the belt 60 and the feeding idle roller 32. Afterwards, a
pair of gear wheels that is driven by a power machine such as a motor
(not shown) is employed to drive the feeding driving roller 31 rotating
in a direction. Then the feeding idle roller 32 is driven rotating by the
feeding driving roller 31 in an opposite direction. Therefore, the
document located between the belt 60 and the feeding idle roller 32 is
flatted and conveyed to the operating passage 102.

[0020]Referring to FIG. 5, the document is conveyed forward along the
operating passage 102 by the belt 60 and the feeding idle roller 32. When
the document is conveyed above the image-handling unit seated in the
recess 12, the image-handling unit provides an image-handling operation
to the document.

[0021]Referring to FIG. 6 and FIG. 7, after the document is handled by the
image-handling unit, the document is transported forward and located
between the drawing-out driving roller 41 and drawing-out idle roller 42.
Then because the belt 60 is put around the feeding driving roller 31 and
the drawing-out driving roller 41, which drives the drawing-out driving
roller 41 rotating in the same direction as the feeding driving roller
31, the drawing-out idle roller 42 is driven rotating by the drawing-out
driving roller 41 in the same direction as the feeding idle roller 32.
Thereby, the document is transported to the exiting passage 103 and
further transported to the outside of the automatic document feeder 1
under the pushing action of the belt 60 and the drawing-out idle roller
42.

[0022]Please refer to FIG. 8. Another embodiment of the present invention
provides an automatic document feeder 1' having a main body 10', a
feeding roller unit 30' and a drawing-out roller unit 40'. The main body
10' defines a passage 105 for transporting a document and a hollow recess
12' at substantially the center thereof for receiving an image-handling
unit (not shown). The feeding roller unit 30' and the drawing-out roller
unit 40' are received in the main body 10'. The feeding roller unit 30'
includes a feeding driving roller 31' and a feeding idle roller 32'. The
feeding driving roller 31' is disposed at an upper side of the passage
105. The feeding idle roller 32' coupling with the feeding driving roller
31' is disposed at a lower side of the passage 105. The drawing-out
roller unit 40' includes a drawing-out driving roller 41' and a
drawing-out idle roller 42'. The drawing-out driving roller 41' is
disposed at the upper side of the passage 105 and parallel with the
feeding driving roller 31'. The drawing-out idle roller 42' coupling with
the drawing-out driving roller 41' is disposed at the lower side of the
passage 105 and parallel with the feeding idle roller 32'. A belt 60' is
put around the feeding driving roller 31' and the drawing-out driving
roller 41' and then mates with the feeding idle roller 32' and the
drawing-out idle roller 42' respectively for flatting and conveying the
document. The processes of the automatic document feeder 1' feeding and
drawing out the document are as the same as the first embodiment of the
present invention, which are not described any more.

[0023]As described above, because the belt 60 is put around the feeding
driving roller 31 and the drawing-out driving roller 41, the automatic
document feeder 1 utilizes one pair of gear wheels to drive the feeding
roller unit 30 and the drawing-out roller unit 40 rotating
simultaneously, and at the same time, the belt 60 flats the document,
which ensures that the document is fed and transported out of the
automatic document feeder 1 smoothly. It is obvious that the automatic
document feeder 1 has a simply structure and it is easy to fabricate the
automatic document feeder 1. Therefore, the manufacture cost of the
automatic document feeder 1 is reduced.

[0024]The foregoing description of the present invention has been
presented for purposes of illustration and description. It is not
intended to be exhaustive or to limit the invention to the precise form
disclosed, and obviously many modifications and variations are possible
in light of the above teaching. Such modifications and variations that
may be apparent to those skilled in the art are intended to be included
within the scope of this invention as defined by the accompanying claims.